This invention relates to a trailer drawbar hinge, and in particular to a tightening mechanism for setting resistance against rotation of the hinge.
When vehicles include multiple trailers the following trailer sometimes is attached to the preceding trailer through a drawbar having a pair of hinge assemblies which allows the drawbar to be lifted on to and off of the pintle of the trailer coupling mounted at the back of the preceding trailer. These hinge assemblies contain a tightening mechanism which allows applying a desired level of resistance against the rotation of the hinge assembly. Examples of these prior art hinges are the Premier Equipment models 320, 440 and 455 hinges. The 450 and 455 hinges provide the resistance by squeezing a pair of bushings radially against a pin which extends through a hole in the bushings. The 320 hinge provides the resistance by pushing a tapered pin into a tapered bore in the bushing. With the former, it is difficult to accurately exert the desired pressure on the pin by the squeezed bushing and with the latter the bushings do not remain centered in the hinge as the amount of resistance is increased.